To evaluate the efficacy of the external application of Sizi powder combined with physiotherapy in the treatment of upper-limb lymphedema after breast cancer surgery.Methods:76 patients with upper limb lymphedema after breast cancer surgery were randomly divided into control group(36 cases)and experiment group(40 cases).Patients in control group received physical therapy(limb massage，function exercise，pressure pump treatment，ect.)while experiment group received external application of Sizi powder as well as physiotherapy.The arm circumference and the pain degree of limb were measured and recorded.Results:Effective rate of experiment group was higher than control group，and the result had significant statistical difference(P=0.041).The pain relief clinical effectiveness compared to no difference in the 2 groups，but the pain in experiment group was alleviated faster than control group， the result also had significant statistical difference(P=0.017).Conclusion:The external application of Sizi powder combined with physiotherapy in the treatment of upper-limb lymphedema after breast cancer surgery had better clinical curative effect.